media: s5p-jpeg: disable encoder/decoder in exynos4-like hardware after use

Clearing the bits turns off the encoder/decoder. If the hardware
is not turned off after use, at subsequent uses it does not work
in a stable manner, resulting in incorrect interrupt status value
being read and e.g. erroneous read of compressed bitstream size.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/platform/s5p-jpeg/jpeg-core.c

@@ -2806,6 +2806,8 @@ static irqreturn_t exynos4_jpeg_irq(int irq, void *priv)
 	if (jpeg->variant->version == SJPEG_EXYNOS4)
 		curr_ctx->subsampling = exynos4_jpeg_get_frame_fmt(jpeg->regs);
 
+	exynos4_jpeg_set_enc_dec_mode(jpeg->regs, S5P_JPEG_DISABLE);
+
 	spin_unlock(&jpeg->slock);
 
 	v4l2_m2m_job_finish(jpeg->m2m_dev, curr_ctx->fh.m2m_ctx);

drivers/media/platform/s5p-jpeg/jpeg-core.h

@@ -63,6 +63,7 @@
 
 #define S5P_JPEG_ENCODE		0
 #define S5P_JPEG_DECODE		1
+#define S5P_JPEG_DISABLE	-1
 
 #define FMT_TYPE_OUTPUT		0
 #define FMT_TYPE_CAPTURE	1

drivers/media/platform/s5p-jpeg/jpeg-hw-exynos4.c

@@ -38,10 +38,13 @@ void exynos4_jpeg_set_enc_dec_mode(void __iomem *base, unsigned int mode)
 		writel((reg & EXYNOS4_ENC_DEC_MODE_MASK) |
 					EXYNOS4_DEC_MODE,
 			base + EXYNOS4_JPEG_CNTL_REG);
-	} else {/* encode */
+	} else if (mode == S5P_JPEG_ENCODE) {/* encode */
 		writel((reg & EXYNOS4_ENC_DEC_MODE_MASK) |
 					EXYNOS4_ENC_MODE,
 			base + EXYNOS4_JPEG_CNTL_REG);
+	} else { /* disable both */
+		writel(reg & EXYNOS4_ENC_DEC_MODE_MASK,
+			base + EXYNOS4_JPEG_CNTL_REG);
 	}
 }